The average journey time comparisons for 1997 to 2007 are listed as follows.
Time 1997 2h 17 1998 2h 17 1999 2h 23 2000 2h 23 2001 2h 23 2002 2h 23 2003 2h 23 2004 2h 01 2005 2h 12 2006 2h 12 2007 2h 12
Time 1997 1h 13 1998 1h 13 1999 1h 16 2000 1h 16 2001 1h 18 2002 1h 16 2003 1h 16 2004 1h 18 2005 1h 19 2006 1h 19 2007 1h 19
The Portsmouth to Waterloo via Eastleigh service has been subject to various stopping patterns. Prior to 2004 it was literally all stations, then became fast from Basingstoke, and now is a semi fast.
The Southampton to Waterloo journey time is based on the fast service and has marginally increased through extended dwell times with the modern stock.